SCT - Thirty Days Later

[Jack B]

I had a few minor software issues initially, but, worked trough them. here is what I have accomplished to this point:

1. Increased the idle to 750.

2. Changed the fan settings for my drag strip tune. I have them (high/low) set so the temp stays at 180 degrees. It does not deviate - it stays right at 180. I have not seen an ambient above 85 degrees, therefore, do not know what will happen at higher temps.

3. Eliminated a hesitation when going to WOT. There are several settings that only allow acceleration enrichment when all the criteria are met. You merely have to relax the criteria. My case was due to larger injectors combined with the VEC. I also added acceleration enrichment fuel. The hesitation is totally gone.


4. Removed all the VEC fuel criteria. Here is the interesting part:

a. With the vec, the a/f line was always ragged when viewed with the Innovate wideband system. You may not see this with other wideband systems since the Innovate polls faster than other systems. The a/f line now looks like a Dynojet graph using the factory PCM and SCT.

b. My car has two widebands, therefore, the logging software displays both a/f lines. For some reason the VEC does not totally sychronize both banks. Banks #2 seems to always lag the Bank #1 a/f line. They look like they are out of sync. With the SCT flashed factory PCM the lines now look like they flow together and are in sync.

c. The VEC must have some unwanted delay in it its algorithem, the typical lean spike wen going to wot and the recovery, is much shorter when the vec is removed.

Lastly, the car has never run stronger and smoother. None of this is meant to demean the VEC, it served its purpose in its time, but, the SCT package does virtually everything better in a shorter time.

 

[99 R/T 10]

Hey Jack,
How hard is it to go fromt he Vec to the SCT? Since I have the tune setup in the Vec, can it be cross loaded into the SCT? Or does it have to be done manually?

 

[eucharistos]

good writeup

thanks

 

[Jack B]

Hey Jack,
How hard is it to go fromt he Vec to the SCT? Since I have the tune setup in the Vec, can it be cross loaded into the SCT? Or does it have to be done manually?

You cannot load it directly into the SCT, but, it is not difficult. The WOT Enrichment table in SCT is a percentage of base injector pulse width. That is much easier to work with than the VEC protocol and easy to convert.

You can get the a/f close, but, I still think it will take a minimum of two or three dyno pulls to nail it down. If you have a wideband it would be as easy as a couple of 2000-5500 (2nd or 3rd gear) safe road pulls. The ignition timing would be simple.

 

[darkostoj]

so what you're saying is the sct is a better overall package than the vec3?

and if you could pick between the two you would do SCT

 

[whitebluevipe]

keep the info. coming. i am very interessted in the sct tuning.

 

[EllowViper]

How do you incorporate the Innovate WB data without the VEC?? I think it is done via Innovate LogWorks and its interoperability with PCMSCAN...Right?? If not, what is your methodology??

 

[FATHERFORD]

I'm confused. Are you using the vec and the SCT or just the SCT now?

 

[ViperTony]

This is great information Jack. I removed my Vec3 a few weeks ago and I'm running without it or an SCT tune, just stock PCM. My hesitation issues when going to WOT are gone. I'm trying to find time to get my SCT dyno-tune done. Glad to see you're making great progress with the SCT so far.

 

[Jack B]

How do you incorporate the Innovate WB data without the VEC?? I think it is done via Innovate LogWorks and its interoperability with PCMSCAN...Right?? If not, what is your methodology??

1. I have always logged with Innovate Logworks. It does far better than the VEC for logging. You can populate a table that has a/f versus rpm and throttle position, then, manually insert those values into SCT. I made a couple more runs today, what a huge difference in drivability and power. I do not know whether it was the VEC or the inability of the VEC to definitively control larger injectors.

2.I ordered/received the PCMCAN, but, it came with a bad interface cable and they have been less than slow to replace it. My experience with Palmer Performance has not been very good. I have always used EASE as a scan tool and it does a good job. It actually has many more parameters/PIDS than PCMSCAN, but, it does not have direct table capability. The PCMSCAN also has a very nice visual layout, I still want to try it, but, dealing with them is like trying to find 380 ammo.

3. I am still using the VEC for the injector proportioning. I have not found an easy way to do that with SCT. the function/table is there, but, it will take a little more work, but, that is my next task.

4. There is no comparison, the SCT package allows you to do far more. I looked at the logs from todays runs, in five years of tuning with the VEC, I was never able to get to such a flat/smooth a/f curve so quickly. When you compare the curves with the VEC to the curves with the SCT, it looks like a different logging software was used.

 

[Jack B]

This is great information Jack. I removed my Vec3 a few weeks ago and I'm running without it or an SCT tune, just stock PCM. My hesitation issues when going to WOT are gone. I'm trying to find time to get my SCT dyno-tune done. Glad to see you're making great progress with the SCT so far.

That sort of points to the VEC as the root of the hesitation. I cannot believe i lived with that hesitation for five years. When I added the mods my power picked up, but my 60 ft times went down because of the hesitation. You still are leaving some hp on the table, SCT is the answer. Both Dan and Britospeed have a lot of SCT experience. You should talk to them or buy the SCT Proracer package.

 

[ViperTony]

That sort of points to the VEC as the root of the hesitation. I cannot believe i lived with that hesitation for five years. When I added the mods my power picked up, but my 60 ft times went down because of the hesitation. You still are leaving some hp on the table, SCT is the answer. Both Dan and Britospeed have a lot of SCT experience. You should talk to them or buy the SCT Proracer package.

Thanks for the advice Jack. I left out a lot of details concerning the hesitation I had and the Vec. Even with the "Stock" Vec tune, I had the hesitation. I don't know if it was the Vec itself, a grounding issue or something else. What was really odd is that in addition to the hesitation I had a "miss" or what I call "fluttering" occuring. Between 4-5K RPM my tach needle would bounce back and forth for a brief a second or two during a WOT pull, on occassion, but it didn't seem to impact driveability. Some told me it was valve float and possibly my valve springs need to be replaced. However, this never happened before I installed the Vec and now doesn't happen since removing it. Don't get me wrong, the Vec worked well and I did pick up good power.

But yes, I'm ready for an SCT. For me being able to tune both closed AND open loop, control the fan turn on temps, lean out my AFR during open loop and make closed loop a little better is all I need, for now. I have a tuner nearby that has a lot of experience with the SCT and tuning with wideband on a dyno. While they've tuned many makes of cars, they've tuned one Viper. At $1,100 for the SCT Tuner + 3.5 hrs of dyno tuning time, I'm not feeling 100% comfortable with them. I may just break down and make the 6 hour trip to see Dan soon.

 

[cyaford]

At $1,100 for the SCT Tuner + 3.5 hrs of dyno tuning time, I'm not feeling 100% comfortable with them.

Hopefully that includes the tuning software.

 

[EllowViper]

Jack,
WIth the Logworks are you running an XD-16 box or some additional Innovate MTS interface? From my understanding, my LC-1 linked to Logworks will just show me the AFR without any association to any other engine attribute (since its not connected to anything but the LC-1 and WB sensor). How are you getting TPS, RPM, timing, etcetera into the Logworks application? Must be with the Ease ODB-II software I'm thinking.

 

[ViperTony]

Hopefully that includes the tuning software.

No, they don't sell the software.

 

[darkostoj]

Jack,
WIth the Logworks are you running an XD-16 box or some additional Innovate MTS interface? From my understanding, my LC-1 linked to Logworks will just show me the AFR without any association to any other engine attribute (since its not connected to anything but the LC-1 and WB sensor). How are you getting TPS, RPM, timing, etcetera into the Logworks application? Must be with the Ease ODB-II software I'm thinking.

i have the lc1/xd16 on my supercharged 67 camaro, but i've never used any of the logging capabilites. Basically from what I understand you can hook up different inputs into the lc1, and you have the choice to log all of these in logworks via laptop. You can do TPS, MAP, a/f, rpm, etc

 

[Tusc]

Tony, who are you thinking of for a local dyno - East Side Performance?

They likely don't have much/any experience with Vipers specifically (who but specialty tuners do?), but they do tune a lot of drag cars and custom Corvettes. I've not come across any negative stories with them and would consider them technically proficient enough to let them play with my car.

Another quasi-local group would be J&M Corvettes in Manchester. I know a lot of guys who have used them and had positive results with all types of cars and setups. Their general rep is good. However, I remember their owner trying to cow a lot of cash out of a friend of mine who didn't know a lick about cars. They hold a decent rep for their work, and I know you're experienced enough to know when someone is running a line, so they might be worth a call if you want to avoid the longer drive.

 

[ViperTony]

Tony, who are you thinking of for a local dyno - East Side Performance?

They likely don't have much/any experience with Vipers specifically (who but specialty tuners do?)

I only want experienced Viper tuners working on my Viper. Period. I can count them on one hand and I'd never let any shop play with my Viper especially when tuning. Case in point, I had one tuner show me the SCT software and try to b.s. me on what some of the parameters did. When I corrected him, he admitted that he had only tuned one Viper with the software and was still 'learning'. THANK YOU AND GOOD BYE. I don't want to divert this thread away from the it's original intent so I'll stop here. Thanks for the info though.

 

[Viper Specialty]

1. I have always logged with Innovate Logworks. It does far better than the VEC for logging. You can populate a table that has a/f versus rpm and throttle position, then, manually insert those values into SCT. I made a couple more runs today, what a huge difference in drivability and power. I do not know whether it was the VEC or the inability of the VEC to definitively control larger injectors.


3. I am still using the VEC for the injector proportioning. I have not found an easy way to do that with SCT. the function/table is there, but, it will take a little more work, but, that is my next task.

1. It has to do with the way the VEC calculates its I/O stream. Unfortunately, it is always a minimum of 1 full revolution behind, hence its lag time. The larger the injector, the worse the problem. Not to mention it does not begin scaling until a certain RPM, which means that Crank Fuel, primeshot, etc are all UNSCALED. Try starting a 96lb injector car with a VEC only, it doesnt work so well!

3. Explain what you mean by injector proportioning. Also, let me know exactly what injectors you have, and I can get you the correct parameters for them so they operate exactly as they should with regard to voltage, min PW, etc.

 

[Viper Specialty]

For anyone who is interested, I will be running a special on the following packages until the end of the month:

1. SCT Programmer w/ up to 3 basic tunes {Additional 100 Off! 449.00!}
2. SCT w/ProRacer {additional 100 bucks off! 849.00!}
3. SCT w/ProRacer & PCMScan {Additional 150 bucks off! 995.00!}

 

[darkostoj]

For anyone who is interested, I will be running a special on the following packages until the end of the month:

1. SCT Programmer w/ up to 3 basic tunes {Additional 100 Off! 449.00!}
2. SCT w/ProRacer {additional 100 bucks off! 849.00!}

so thats everything you need to get tuning for $850? I may do this

 

[Viper Specialty]

so thats everything you need to get tuning for $850? I may do this

If you dont need to do Closed Loop fine tuning, then yes it is! If you need to do Closed Loop, you will need some sort of scanning software of scan tool, such as Ease or PCMSCAN.

[Added the above package]

 

[darkostoj]

If you dont need to do Closed Loop fine tuning, then yes it is! If you need to do Closed Loop, you will need some sort of scanning software of scan tool, such as Ease or PCMSCAN.

[Added the above package]

could you clarify what the PCMSCAN actually does and why you need it for closed loop tuning? Closed loop is all other times than WOT correct?

 

[Viper Specialty]

could you clarify what the PCMSCAN actually does and why you need it for closed loop tuning? Closed loop is all other times than WOT correct?

It allows you to scan all PCM parameters as the engine is running and log them into tables for reference later. You need to be able to scan the PCM's long or short term fuel adaptives in order to build base fuel map tables BEFORE tuning WOT [if you need work on closed loop]

Yes, Closed Loop is all times except for Warm-Up, and when fuel enrichment is occuring.

 

[darkostoj]

It allows you to scan all PCM parameters as the engine is running and log them into tables for reference later. You need to be able to scan the PCM's long or short term fuel adaptives in order to build base fuel map tables BEFORE tuning WOT [if you need work on closed loop]

Yes, Closed Loop is all times except for Warm-Up, and when fuel enrichment is occuring.

so basically pcmscan for tuning closed loop is a must.

Right now I have a bolt on gts, but will go to forced induction within the year. I already have a lc1/xd16 wideband. Will I be able to stay with the SCT, or will I have to go to something like a vec or AEM?

 

[Viper Specialty]

so basically pcmscan for tuning closed loop is a must.

Right now I have a bolt on gts, but will go to forced induction within the year. I already have a lc1/xd16 wideband. Will I be able to stay with the SCT, or will I have to go to something like a vec or AEM?

The SCT can tune FI cars if you learn the system well enough. However, another method is the SCT/VEC combo. When using them both, you will have full tuning capability and resolution, and can easily tune for boost once the factory PCM is set up the way you want it, and it will be just as smooth as the VEC is not scaling injectors or removing fuel.

 

[eucharistos]

For anyone who is interested, I will be running a special on the following packages until the end of the month:

1. SCT Programmer w/ up to 3 basic tunes {Additional 100 Off! 449.00!}
2. SCT w/ProRacer {additional 100 bucks off! 849.00!}
3. SCT w/ProRacer & PCMScan {Additional 150 bucks off! 995.00!}

good prices

 

[plumcrazy]

Tony, youre best bet is dive north to let dan install and tune.

 

[ViperJohn]

Just curious what version of the EASE Diagnosics everyone is using. I have it, but it logs the data in different values than what the PCM looks for. Example: Map sensor is logs pressure yet PCM looks for voltage.

 

[Viper Specialty]

Just curious what version of the EASE Diagnosics everyone is using. I have it, but it logs the data in different values than what the PCM looks for. Example: Map sensor is logs pressure yet PCM looks for voltage.

The PCM always looks at voltage, it is up to the software to interpret the inputs.